Aerial warning marker



J1me 1964 .1. R. PFEIFFER ETAL 3,135,236

AERIAL WARNING MARKER Filed March 27, 1961 Jack R. Pf'eiffer Harold E.Backen INVENTORS United States Patent "ice 3,135,236 AERIAL WARNING MARKER Jack Russell Pfeiifer and Harold E. Backeu, both of Roseburg, 0reg., assignors to Pacific Plywood Co., Dillard, Greg, a corporation of Oregon Filed Mar. 27, 1961, Ser. No. 98,533 1 Claim. (Cl. 116-114) This invention relates to aerial warning markers.

The marking of power transmission lines, tower guy lines, towers, and other aerial installations to provide effective danger signals for observation by the operators of aircraft, high cranes, etc. presents a difiicult problem because of the inaccessibility of the installations and the high voltage which they may carry.

Accordingly the general object of the present invention is to provide a warning marker for use on such installations which may be installed easily, even on hot lines, and which is characterized further by being:

(1) Readily visible from a great distance.

(2) Permanently colored.

(3) Free from the tendency to abrade or fatigue the cable when blown about by the wind.

(4) Safely applicable to electrical cables without stopping the flow of electricity.

5) Easily releasable from bodies of water in which they may become partly submerged during installation or otherwise.

(6) Substantially indestructible, even though subjected to abuse and gunfire by target-shooting gun enthusiasts.

(7) Self-cleaning with respect to icicles which may form on it. 1

(8) Readily producible in a variety of sizes and nesting shapes for convenient and low cost transportation and storage.

The manner in which the foregoing and other objects of this invention are accomplished will be apparent from the accompanying specification and claim considered together with the drawings, wherein:

FIG. 1 is a view in elevation of the presently described aerial cable warning marker in a first embodiment;

FIG. 2 is a fragmentary cross sectional View taken along line 2-2 of FIG. 1;

FIG. 3 is a fragmentary view in side elevation, partly in section, of an alternate form of connector for use in the herein described warning marker;

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a fragmentary view in side elevation, partly in section, of still another form of connector for use in the herein described warning marker; and

FIG. 6 is a cross sectional view taken along line 66 of FIG. 5.

Generally considered, the aerial cable warning marker of our invention comprises a marker body having attention-attracting physical characteristics, a flexible connector, means for fastening one end of the connector to the marker body, and securing means for securing the other end of the connector to the cable. The body may assume various sizes and shapes, and the flexible connector may be employed in various embodiments as appear below.

In the form of the invention illustrated in FIGS. 1 and 2, the warning marker is applied to a cable 10 which may comprise a power transmission line or guy line requiring marking for making airplane pilots, crane operators and other personnel aware of the hazard. The marker includes a body 12 which may be of any desired size, configuration, color and material.

Preferably, the body comprises a hollow, truncated cone of fiberglass pigmented with orange or other selected bright color. The cone is hollow, open at its bottom,

3,135,236 Patented June 2, 1964 and either open or closed at its top. When the top is closed vent holes 14 preferably are included.

These serve a suction breaking function in the event that the open bottom end of the cone is submerged in water, as may occur when the power line is located across a reservoir or other body of water and is lowered to the water surface for afiixing the markers. They also allow for air passage in high winds.

The body 12 of the marker is connected to the cable by means of a flexible connector, preferably a flexible coil spring 16. The lower end of this spring is fastened to the top of the body by means of a bolt 18.

The pitch of the threads of bolt 18 is such that it matches the pitch of the windings of coil spring 16. Hence the bolt may be threaded into the end of the spring. The union becomes permanent because, although the bolt may be screwed easily into the spring, an attempt to unscrew it results in tightening down of the coils of the spring on the bolt threads, locking the spring securely to the bolt.

Bolt 18 is threaded into spring 16 until the lower end of the spring abuts the top of the cone. Washers 20, 22 or suitably sized jam nuts are interposed to strengthen the connection.

The upper end of flexible connector 16 is attached to the cable by means of a cleft-head bolt indicated generally at 24. The stem 26 of the bolt is provided with threads having a pitch corresponding to the pitch of the spring and hence may be threaded into the latter until bolt head 28 abuts against the upper end of the spring. A selflocking union thus is achieved, in the manner explained above with respect to bolt 18.

Head 28 of bolt 24 is cleft or bifurcated to provide a recess 30 of sufiicient width to receive cable 10. The upper end of the head is externally threaded and provided with a nut 32 which carries a central, swiveling core 34. Thus when the cable lies within cleft 30, as illustrated in FIG. 2, nut 32 may be screwed downwardly until swiveling core 34 bears against the cable. This anchors the marker securely in the desired location.

In the form of the invention illustrated in FIGS. 3 and 4, a different type of connector is used to fasten the marker to the cable. In this form of the invention flexible coil spring 16 is fastened to the top of cone 12 by means of bolt 18 and washers 20, 22, as heretofore described. However, threaded into the upper end of spring 16 is a bolt indicated at 40. It comprises a threaded stem section 42 which is threaded into the spring until the top of the latter abuts head 44 of the bolt. The bolt head is formed with an extension 46 on which is threaded the stem 48 of a compression type T connector 50.

As shown in FIG. 4, the crosshead of the connector is formed in two pieces 52, 54 so dimensioned that the overlying piece 54 receives cable 10 and is crimped against the underlying piece 52 by the application of a suitable crimping tool.

Still another form of connector is illustrated in FIGS. 5 and 6. Again bolt 18 penetrates an opening in the top of the marking cone and is threaded into a flexible coil spring 16, washers 20, 22 being interposed to strengthen the connection.

However, the upper end of spring 16 is fastened to cable 10 through the agency of a bolt 60 formed in the shape of a T bar. The threaded stem 62 of the bolt is screwed into the open upper end of spring 16. Its crossbar 64 is of sufficient extent so that each end can be received in one of a pair of duplex compression connectors 66.

The character of these connectors is such that one side may be placed around crossbar 64 of bolt 60 while the other side may be placed around cable 10. The con- 3, nectors may be pressed into clamping engagement with these two members by use of a suitable tool, thereby anchoring the marker at the selected location along cable 10.

In the application of the presently described warning markers, cable l0 which may be a high power transmission line spanning a lake or reservoir, may be lowered until it is close to the water surface. The markers then may be aflixed to the cable at predetermined intervals, using any of the clamping means illustrated above. The line then may be hoisted to the desired elevation. In the event that the markers are in the shape of hollow cones, the open, lower ends of which have settled below the level of the water, vents 14 provide access for air, breaking the suction that otherwise would develop within the cone and permitting elevaticnof the cable and markers in the desired manner.

When in position on the cable, the markers aflford a warning signal for approaching aircraft. Their eifective- -ness is augmented by their size, shape, distinctive color,

and particularly by the flexibility of springs '16 and their depending connection which permits the markers to move back and forth in the wind, thereby animating them. Such animation h'as the further desirable effect of breaking 01f icicles which may form on the marker in the winter time. Since the upper end of the connector is rigid with the cable movement of the marker is accomplished without wearing or fatiguing the cable.

In addition, the service life of the marker is rendered unusually long by the use of a pigmented plastic, Which retains its color permanently, as well as by the use of a non-shatterable material which is resistant to both gun- 'fire and the normal wear caused by movement of the marker relative to the cable.

It is to be understood that the forms of our invention herein shown and described are to be taken as preferred examples of the same and that various other changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of our invention or the scope of the subjoined claim.

Having thus described our invention, we claim:

An aerial cable warning marker comprising an attention-attracting marker body having a top end wall, an elongated coil spring secured at one end firmly to said top end wall and projecting upward therefrom, fastener means secured firmly to the opposite end of said coil spring and including a clamping section adapted to be secured firmly to an aerial cable against rotation thereon, in the direction normal to its longitudinal axis to-permit back and forth swinging of the marker body relative to the fastener means.

References Cited in the file of this patent UNITED STATES PATENTS 517,548 Herwe'ye'r Apr. 3, 1894 851,012 Lanius Apr. 23, 1907 911,991 Igelstroem Feb. 9, 1909 1,195,171 Bacon et al Aug. 22, 1916 1,828,892 Felton Oct. 27, 1931 1,861,532 Hough June 7, 1932 2,000,491 Manor Q. May 7, 1935 2,050,579 Murray Aug. 11, 1936 2,352,318 Guarnaschelli June 27, 1 944 2,646,638 Peterson July 28, 1953 2,658,467 Trapani Nov. 10, 1953 2,762,328 Weig Sept. 11, 1956 Y 2,817,308 Scalon Dec. 24, 1957 2,965,892 Langdon Dec. 20, 1960 3,016,035 Asbury Jan. 9, 1962 FOREIGN PATENTS 665,785 Great Britain Jan. 30, 1952 

